Diagnosis and New Treatment Avenues in Spinal Muscular Atrophy

Abstract Spinal muscular atrophy (SMA) is an autosomal-recessive, neuromuscular disorder that is characterized by degeneration of the anterior horn cells of the spinal cord, resulting in muscle atrophy and proximal muscle weakness. SMA is caused by a homozygous deletion in the survival motor neuron 1 (SMN1) gene on chromosome 5q13. The SMN gene region also comprises a centromeric copy containing the SMN2 gene. The severity of the disease correlates with age of onset and SMN2 copy number and varies from a severe muscle weakness with tetraplegia in infants to a mild proximal muscle weakness in ambulant children. Due to lack of a curative treatment, the care of children with SMA consists mostly of a multidisciplinary treatment including respiratory, nutritional, and orthopaedic management. During the past years, there has been a promising approach for the development of drugs intervening the pathophysiology of SMA with the main idea of upregulating the levels of functional SMN protein. Here, we summarize recent studies regarding diagnosis and treatment avenues in SMA.